<!DOCTYPE html>
<html lang="en" xmlns:v-on="http://www.w3.org/1999/xhtml">
<head>
    <meta charset="UTF-8">
    <title>事件</title>
</head>
<body>
    <div id="app">
        <input placeholder="请输入你的自行车数量" v-model="num"/><br/>
        我有{{num}}辆自行车<br/>
        yyy{{hello}}xxxx
        <button v-on:mouseenter="num++">增加自行车数量</button>
        <button v-on:mouseout="num--">减少自行车数量</button>
    </div>


    {{num}}
    <script src="../node_modules/vue/dist/vue.js"></script>
    <script>
        let app = new Vue({
            el:"#app",
            data:{
                num:1,
                hello:""
            }
        })


    </script>
</body>
</html>